tproxy: added IPv6 support to the socket match (b64c9256) · Commits · EulixOS / Software / Kernel

net/netfilter/xt_socket.c

+154 −11

Original line number	Diff line number	Diff line
		@@ -14,6 +14,7 @@
		#include <linux/skbuff.h>
		#include <linux/netfilter/x_tables.h>
		#include <linux/netfilter_ipv4/ip_tables.h>
		#include <linux/netfilter_ipv6/ip6_tables.h>
		#include <net/tcp.h>
		#include <net/udp.h>
		#include <net/icmp.h>
		@@ -21,6 +22,7 @@
		#include <net/inet_sock.h>
		#include <net/netfilter/nf_tproxy_core.h>
		#include <net/netfilter/ipv4/nf_defrag_ipv4.h>
		#include <net/netfilter/ipv6/nf_defrag_ipv6.h>

		#include <linux/netfilter/xt_socket.h>

		@@ -30,7 +32,7 @@
		#endif

		static int
		extract_icmp_fields(const struct sk_buff *skb,
		extract_icmp4_fields(const struct sk_buff *skb,
		u8 *protocol,
		__be32 *raddr,
		__be32 *laddr,
		@@ -86,7 +88,6 @@ extract_icmp_fields(const struct sk_buff *skb,
		return 0;
		}


		static bool
		socket_match(const struct sk_buff skb, struct xt_action_param par,
		const struct xt_socket_mtinfo1 *info)
		@@ -115,7 +116,7 @@ socket_match(const struct sk_buff skb, struct xt_action_param par,
		dport = hp->dest;

		} else if (iph->protocol == IPPROTO_ICMP) {
		if (extract_icmp_fields(skb, &protocol, &saddr, &daddr,
		if (extract_icmp4_fields(skb, &protocol, &saddr, &daddr,
		&sport, &dport))
		return false;
		} else {
		@@ -165,32 +166,157 @@ socket_match(const struct sk_buff skb, struct xt_action_param par,
		sk = NULL;
		}

		pr_debug("proto %u %08x:%u -> %08x:%u (orig %08x:%u) sock %p\n",
		protocol, ntohl(saddr), ntohs(sport),
		ntohl(daddr), ntohs(dport),
		ntohl(iph->daddr), hp ? ntohs(hp->dest) : 0, sk);
		pr_debug("proto %hhu %pI4:%hu -> %pI4:%hu (orig %pI4:%hu) sock %p\n",
		protocol, &saddr, ntohs(sport),
		&daddr, ntohs(dport),
		&iph->daddr, hp ? ntohs(hp->dest) : 0, sk);

		return (sk != NULL);
		}

		static bool
		socket_mt_v0(const struct sk_buff skb, struct xt_action_param par)
		socket_mt4_v0(const struct sk_buff skb, struct xt_action_param par)
		{
		return socket_match(skb, par, NULL);
		}

		static bool
		socket_mt_v1(const struct sk_buff skb, struct xt_action_param par)
		socket_mt4_v1(const struct sk_buff skb, struct xt_action_param par)
		{
		return socket_match(skb, par, par->matchinfo);
		}

		#if defined(CONFIG_IPV6) \|\| defined(CONFIG_IPV6_MODULE)

		static int
		extract_icmp6_fields(const struct sk_buff *skb,
		unsigned int outside_hdrlen,
		u8 *protocol,
		struct in6_addr **raddr,
		struct in6_addr **laddr,
		__be16 *rport,
		__be16 *lport)
		{
		struct ipv6hdr *inside_iph, _inside_iph;
		struct icmp6hdr *icmph, _icmph;
		__be16 *ports, _ports[2];
		u8 inside_nexthdr;
		int inside_hdrlen;

		icmph = skb_header_pointer(skb, outside_hdrlen,
		sizeof(_icmph), &_icmph);
		if (icmph == NULL)
		return 1;

		if (icmph->icmp6_type & ICMPV6_INFOMSG_MASK)
		return 1;

		inside_iph = skb_header_pointer(skb, outside_hdrlen + sizeof(_icmph), sizeof(_inside_iph), &_inside_iph);
		if (inside_iph == NULL)
		return 1;
		inside_nexthdr = inside_iph->nexthdr;

		inside_hdrlen = ipv6_skip_exthdr(skb, outside_hdrlen + sizeof(_icmph) + sizeof(_inside_iph), &inside_nexthdr);
		if (inside_hdrlen < 0)
		return 1; /* hjm: Packet has no/incomplete transport layer headers. */

		if (inside_nexthdr != IPPROTO_TCP &&
		inside_nexthdr != IPPROTO_UDP)
		return 1;

		ports = skb_header_pointer(skb, inside_hdrlen,
		sizeof(_ports), &_ports);
		if (ports == NULL)
		return 1;

		/* the inside IP packet is the one quoted from our side, thus
		* its saddr is the local address */
		*protocol = inside_nexthdr;
		*laddr = &inside_iph->saddr;
		*lport = ports[0];
		*raddr = &inside_iph->daddr;
		*rport = ports[1];

		return 0;
		}

		static bool
		socket_mt6_v1(const struct sk_buff skb, struct xt_action_param par)
		{
		struct ipv6hdr *iph = ipv6_hdr(skb);
		struct udphdr _hdr, *hp = NULL;
		struct sock *sk;
		struct in6_addr daddr, saddr;
		__be16 dport, sport;
		int thoff;
		u8 tproto;
		const struct xt_socket_mtinfo1 info = (struct xt_socket_mtinfo1 ) par->matchinfo;

		tproto = ipv6_find_hdr(skb, &thoff, -1, NULL);
		if (tproto < 0) {
		pr_debug("unable to find transport header in IPv6 packet, dropping\n");
		return NF_DROP;
		}

		if (tproto == IPPROTO_UDP \|\| tproto == IPPROTO_TCP) {
		hp = skb_header_pointer(skb, thoff,
		sizeof(_hdr), &_hdr);
		if (hp == NULL)
		return false;

		saddr = &iph->saddr;
		sport = hp->source;
		daddr = &iph->daddr;
		dport = hp->dest;

		} else if (tproto == IPPROTO_ICMPV6) {
		if (extract_icmp6_fields(skb, thoff, &tproto, &saddr, &daddr,
		&sport, &dport))
		return false;
		} else {
		return false;
		}

		sk = nf_tproxy_get_sock_v6(dev_net(skb->dev), tproto,
		saddr, daddr, sport, dport, par->in, NFT_LOOKUP_ANY);
		if (sk != NULL) {
		bool wildcard;
		bool transparent = true;

		/* Ignore sockets listening on INADDR_ANY */
		wildcard = (sk->sk_state != TCP_TIME_WAIT &&
		ipv6_addr_any(&inet6_sk(sk)->rcv_saddr));

		/* Ignore non-transparent sockets,
		if XT_SOCKET_TRANSPARENT is used */
		if (info && info->flags & XT_SOCKET_TRANSPARENT)
		transparent = ((sk->sk_state != TCP_TIME_WAIT &&
		inet_sk(sk)->transparent) \|\|
		(sk->sk_state == TCP_TIME_WAIT &&
		inet_twsk(sk)->tw_transparent));

		nf_tproxy_put_sock(sk);

		if (wildcard \|\| !transparent)
		sk = NULL;
		}

		pr_debug("proto %hhu %pI6:%hu -> %pI6:%hu "
		"(orig %pI6:%hu) sock %p\n",
		tproto, saddr, ntohs(sport),
		daddr, ntohs(dport),
		&iph->daddr, hp ? ntohs(hp->dest) : 0, sk);

		return (sk != NULL);
		}
		#endif

		static struct xt_match socket_mt_reg[] __read_mostly = {
		{
		.name = "socket",
		.revision = 0,
		.family = NFPROTO_IPV4,
		.match = socket_mt_v0,
		.match = socket_mt4_v0,
		.hooks = (1 << NF_INET_PRE_ROUTING) \|
		(1 << NF_INET_LOCAL_IN),
		.me = THIS_MODULE,
		@@ -199,17 +325,33 @@ static struct xt_match socket_mt_reg[] __read_mostly = {
		.name = "socket",
		.revision = 1,
		.family = NFPROTO_IPV4,
		.match = socket_mt_v1,
		.match = socket_mt4_v1,
		.matchsize = sizeof(struct xt_socket_mtinfo1),
		.hooks = (1 << NF_INET_PRE_ROUTING) \|
		(1 << NF_INET_LOCAL_IN),
		.me = THIS_MODULE,
		},
		#if defined(CONFIG_IPV6) \|\| defined(CONFIG_IPV6_MODULE)
		{
		.name = "socket",
		.revision = 1,
		.family = NFPROTO_IPV6,
		.match = socket_mt6_v1,
		.matchsize = sizeof(struct xt_socket_mtinfo1),
		.hooks = (1 << NF_INET_PRE_ROUTING) \|
		(1 << NF_INET_LOCAL_IN),
		.me = THIS_MODULE,
		},
		#endif
		};

		static int __init socket_mt_init(void)
		{
		nf_defrag_ipv4_enable();
		#if defined(CONFIG_IPV6) \|\| defined(CONFIG_IPV6_MODULE)
		nf_defrag_ipv6_enable();
		#endif

		return xt_register_matches(socket_mt_reg, ARRAY_SIZE(socket_mt_reg));
		}

		@@ -225,3 +367,4 @@ MODULE_LICENSE("GPL");
		MODULE_AUTHOR("Krisztian Kovacs, Balazs Scheidler");
		MODULE_DESCRIPTION("x_tables socket match module");
		MODULE_ALIAS("ipt_socket");
		MODULE_ALIAS("ip6t_socket");